About a half a cup per day--less than what a Vietnamese child might eat--of this "golden" rice can provide all the daily vitamin A a person needs. That's important for people whose primary food is rice, a poor source of essential nutrients. About half a million children go blind every year from vitamin A deficiency.

The technological breakthrough for golden rice came back in 1999, and the crop quickly became a symbol for those who believe in the lifesaving potential of GM crops. But political hurdles delayed field-testing by eight years. In 2008 the rice's developers, the Golden Rice Humanitarian Board, finally received clearance in the Philippines to conduct field trials. The group is fighting for regulatory clearance in six other southeast Asian countries.